1. Technical Field
The present invention relates generally to the Internet of Things (IoT) and, more particularly, to technology for the network management of the IoT.
2. Description of the Related Art
Research on IoT started from a concept of assigning information processing function, data transmission and reception functions to things and connecting the things to a public network, such as the Internet, and has explosively proliferated through fusion with other concepts, such as a mobile network, smart phones, ubiquitous network, sensor network, big data technology, etc.
Although a situation varies depending on the intrinsic function and shape of a thing, a device having a network function (hereinafter referred to as a “network function device”) may be supposedly a device that operates based on a battery in order to attach such a network function device to a thing which is mobile, portable, or non-grid, while maintaining the function and shape of the thing.
Since the capabilities of the IoT increase in proportion to the number of things it is connected with, the energy efficiency of network function devices attached to respective things is a matter of great concern.
In general, the energy efficiency of a network function device, i.e., a node, attached to a thing is dependent on the power consumption during transmission and reception operations, rather than the power consumption during information collection operations and command processing operations. Although the dissipated power of transmission and reception operations are determined by various factors, such as transmission distance, bit error rate (BER), transmission protocols, etc., a factor that greatly influences the energy over a long period of time is also the number of transmissions.
Since a sub-node, a node among IoT nodes consisting a sub-network, which functions as a gateway to an upper layer, must transmit data collected from other sub-nodes to the upper layer, and transmit network management information and commands received from the upper layer to other sub-nodes, the sub-node should perform transmission operations much more than other sub-nodes do. As a result, the energy of the battery of the specific sub-node functioning as a gateway will be consumed earlier, and therefore the sub-network will not function normally. This phenomenon is called as energy hole problem.
In particular, network management information, such as firmware update, security data, network configuration information, etc., which must be transmitted to all sub-nodes from upper layer may rapidly consume the battery of a specific sub-node that functions as a gateway.
Therefore, there is a need for a method for propagating network management information to sub-nodes that constitute the IoT in an energy-efficient manner.